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1.
Psychol Med ; 54(4): 835-846, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37655520

ABSTRACT

BACKGROUND: The ability to extinguish a maladaptive conditioned fear response is crucial for healthy emotional processing and resiliency to aversive experiences. Therefore, enhancing fear extinction learning has immense potential emotional and health benefits. Mindfulness training enhances both fear conditioning and recall of extinguished fear; however, its effects on fear extinction learning are unknown. Here we investigated the impact of mindfulness training on brain mechanisms associated with fear-extinction learning, compared to an exercise-based program. METHODS: We investigated BOLD activations in response to a previously learned fear-inducing cue during an extinction paradigm, before and after an 8-week mindfulness-based stress reduction program (MBSR, n = 49) or exercise-based stress management education program (n = 27). RESULTS: The groups exhibited similar reductions in stress, but the MBSR group was uniquely associated with enhanced activation of salience network nodes and increased hippocampal engagement. CONCLUSIONS: Our results suggest that mindfulness training increases attention to anticipatory aversive stimuli, which in turn facilitates decreased aversive subjective responses and enhanced reappraisal of the memory.


Subject(s)
Fear , Mindfulness , Humans , Fear/physiology , Extinction, Psychological/physiology , Brain , Mental Recall/physiology , Magnetic Resonance Imaging
2.
Neurol Sci ; 45(1): 269-276, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37578630

ABSTRACT

BACKGROUND AND OBJECTIVE: Previous studies have shown that the salience network (SN) and the thalamus are involved in cluster headache (CH) attacks. However, very little is known regarding the altered thalamus-SN functional connectivity in CH. The aim of this study was to explore alterations of functional connectivity between the thalamus and the SN in patients with CH to further gain insight into the pathophysiology of CH. MATERIALS AND METHODS: The resting-state functional MRI (rs-fMRI) data of 21 patients with CH in the headache attack remission state during in-bout periods and 21 age- and sex-matched normal controls were obtained. The rs-fMRI data were analyzed by the independent component analysis (ICA) method, and the thalamus-SN functional connectivity in patients with right-sided and left-sided CH was compared with that in normal controls. RESULTS: Decreased functional connectivity was found between the thalamus, both ipsilateral and contralateral to the headache side, and the SN during headache remission state in both right-sided CH patients and left-sided CH patients. CONCLUSIONS: The findings suggest that the decreased functional connectivity between the thalamus and SN might be one of the pathologies underpinning the CH. This helps us to understand better the nature of the brain dysfunction in CH and the basic pathologies of CH, which implies that this deserves further investigation.


Subject(s)
Cluster Headache , Humans , Cluster Headache/diagnostic imaging , Pilot Projects , Magnetic Resonance Imaging/methods , Thalamus/diagnostic imaging , Headache , Brain/diagnostic imaging
3.
Front Psychiatry ; 14: 1123204, 2023.
Article in English | MEDLINE | ID: mdl-37484679

ABSTRACT

Background: Increased mindfulness is associated with reduced alcohol consumption in patients with alcohol use disorder (AUD) after residential treatment. However, the underlying neurobiological mechanism of mindfulness in AUD is unclear. Therefore, we investigate the structural and functional alterations of the thalamocortical system with a focus on the mediodorsal thalamic nucleus (MD-TN), the default mode and the salience network (DMN/SN) which has previously been associated with mindfulness in healthy subjects. We hypothesized lower mindfulness and reduced structural and functional connectivity (FC) of the thalamocortical system, particularly in the DMN/SN in AUD. We assumed that identified neurobiological alterations in AUD are associated with impairments of mindfulness. Methods: Forty-five abstinent patients with AUD during residential treatment and 20 healthy controls (HC) were recruited. Structural and resting-state functional MRI-scans were acquired. We analysed levels of mindfulness, thalamic volumes and network centrality degree of the MD-TN using multivariate statistics. Using seed-based whole brain analyses we investigated functional connectivity (FC) of the MD-TN. We performed exploratory correlational analyses of structural and functional DMN/SN measurements with levels of mindfulness. Results: In AUD we found significantly lower levels of mindfulness, lower bilateral thalamic and left MD-TN volumes, reduced FC between MD-TN and anterior cingulum/insula and lower network centrality degree of the left MD-TN as compared to HC. In AUD, lower mindfulness was associated with various reductions of structural and functional aspects of the MD-TN. Conclusion: Our results suggest that structural and functional alterations of a network including the MD-TN and the DMN/SN underlies disturbed mindfulness in AUD.

4.
Article in English | MEDLINE | ID: mdl-35108587

ABSTRACT

Background It is gradually becoming clear that obsessive-compulsive disorder (OCD) patients have aberrant resting-state large-scale intrinsic networks of cingulo-opercular salience (SN), default mode (DMN), and front-parietal network (FPN). However, it remains unknown whether unaffected first-degree relatives of OCD patients have these alterations as a vulnerability marker to the disorder. Methods We performed resting-state functional magnetic resonance imaging (rsfMRI) scans of 47 medication-free OCD patients, 21 unaffected healthy first-degree relatives of OCD patients, and 62 healthy control (HC) participants. We explored differences between the three groups in the functional connectivity from SN (seeds: anterior-insula (AI) and dorsal anterior cingulate cortex (dACC)), DMN (seeds: medial prefrontal cortex (MPFC) and posterior parietal cortex (PCC)), and FPN (seeds: dorsolateral prefrontal cortex (DLPFC)). Results Compared to HC, both OCD patients and first-degree relatives showed significantly greater functional connectivity between AI and PCC and between DLPFC and the thalamus. Compared to first-degree relatives and HC, OCD patients showed reduced functional connectivity between PCC and DLPFC, and this altered functional connectivity was negatively correlated with anxiety and depressive symptom within OCD group. Conclusions OCD patients and unaffected first-degree relatives of OCD patients showed overlapping alterations in resting state functional connectivity between the regions of SN and DMN and between DLPFC and the thalamus. Our results suggested that alterations between large-scale intrinsic networks and within the dorsal cognitive cortico-striato-thalamo-cortical (CSTC) circuit could represent endophenotype markers of OCD.


Subject(s)
Endophenotypes , Obsessive-Compulsive Disorder , Brain Mapping , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Neural Pathways/diagnostic imaging , Obsessive-Compulsive Disorder/diagnostic imaging , Obsessive-Compulsive Disorder/genetics , Thalamus
5.
Neurosci Biobehav Rev ; 135: 104583, 2022 04.
Article in English | MEDLINE | ID: mdl-35202647

ABSTRACT

This review synthesizes relations between mindfulness and resting-state fMRI functional connectivity of brain networks. Mindfulness is characterized by present-moment awareness and experiential acceptance, and relies on attention control, self-awareness, and emotion regulation. We integrate studies of functional connectivity and (1) trait mindfulness and (2) mindfulness meditation interventions. Mindfulness is related to functional connectivity in the default mode (DMN), frontoparietal (FPN), and salience (SN) networks. Specifically, mindfulness-mediated functional connectivity changes include (1) increased connectivity between posterior cingulate cortex (DMN) and dorsolateral prefrontal cortex (FPN), which may relate to attention control; (2) decreased connectivity between cuneus and SN, which may relate to self-awareness; (3) increased connectivity between rostral anterior cingulate cortex region and dorsomedial prefrontal cortex (DMN) and decreased connectivity between rostral anterior cingulate cortex region and amygdala region, both of which may relate to emotion regulation; and lastly, (4) increased connectivity between dorsal anterior cingulate cortex (SN) and anterior insula (SN) which may relate to pain relief. While further study of mindfulness is needed, neural signatures of mindfulness are emerging.


Subject(s)
Magnetic Resonance Imaging , Mindfulness , Brain/physiology , Brain Mapping , Gyrus Cinguli/diagnostic imaging , Humans , Prefrontal Cortex/physiology
6.
Hum Brain Mapp ; 43(3): 974-984, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34816523

ABSTRACT

Recent evidence suggests that presupplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) play an important role in response inhibition. However, no study has investigated the relationship between these brain networks at resting-state and response inhibition in obsessive-compulsive disorder (OCD). We performed resting-state functional magnetic resonance imaging scans and then measured the response inhibition of 41 medication-free OCD patients and 49 healthy control (HC) participants by using the stop-signal task outside the scanner. We explored the differences between OCD and HC groups in the functional connectivity of pre-SMA and IFG associated with the ability of motor response inhibition. OCD patients showed a longer stop-signal reaction time (SSRT). Compared to HC, OCD patients exhibit different associations between the ability of motor response inhibition and the functional connectivity between pre-SMA and IFG, inferior parietal lobule, dorsal anterior cingulate cortex, insula, and anterior prefrontal cortex. Additional analysis to investigate the functional connectivity difference from the seed ROIs to the whole brain voxels revealed that, compared to HC, OCD exhibited greater functional connectivity between pre-SMA and IFG. Also, this functional connectivity was positively correlated with the SSRT score. These results provide additional insight into the characteristics of the resting-state functional connectivity of the regions belonging to the cortico-striato-thalamo-cortical circuit and the cingulo-opercular salience network, underlying the impaired motor response inhibition of OCD. In particular, we emphasize the importance of altered functional connectivity between pre-SMA and IFG for the pathophysiology of motor response inhibition in OCD.


Subject(s)
Cerebral Cortex/physiopathology , Connectome , Corpus Striatum/physiopathology , Inhibition, Psychological , Motor Activity/physiology , Motor Cortex/physiopathology , Nerve Net/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Thalamus/physiopathology , Adult , Cerebral Cortex/diagnostic imaging , Corpus Striatum/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Motor Cortex/diagnostic imaging , Nerve Net/diagnostic imaging , Obsessive-Compulsive Disorder/diagnostic imaging , Thalamus/diagnostic imaging , Young Adult
7.
Front Psychol ; 12: 745344, 2021.
Article in English | MEDLINE | ID: mdl-34867626

ABSTRACT

Purpose: The purpose of this study was to investigate the effect of an intensive 8-day Samyama meditation program on the brain functional connectivity using resting-state functional MRI (rs-fMRI). Methods: Thirteen Samyama program participants (meditators) and 4 controls underwent fMRI brain scans before and after the 8-day residential meditation program. Subjects underwent fMRI with a blood oxygen level dependent (BOLD) contrast at rest and during focused breathing. Changes in network connectivity before and after Samyama program were evaluated. In addition, validated psychological metrics were correlated with changes in functional connectivity. Results: Meditators showed significantly increased network connectivity between the salience network (SN) and default mode network (DMN) after the Samyama program (p < 0.01). Increased connectivity within the SN correlated with an improvement in self-reported mindfulness scores (p < 0.01). Conclusion: Samyama, an intensive silent meditation program, favorably increased the resting-state functional connectivity between the salience and default mode networks. During focused breath watching, meditators had lower intra-network connectivity in specific networks. Furthermore, increased intra-network connectivity correlated with improved self-reported mindfulness after Samyama. Clinical Trials Registration: [https://clinicaltrials.gov], Identifier: [NCT04366544]. Registered on 4/17/2020.

8.
Neurobiol Aging ; 103: 12-21, 2021 07.
Article in English | MEDLINE | ID: mdl-33774574

ABSTRACT

The occurrence of a very infrequent and unattended auditory stimulus is highly salient and may result in an interruption of the frontoparietal network controlling processing priorities. Research has suggested that older adults may be unable to compute the level of salience of unattended stimulus inputs. A multi-channel EEG was recorded in 20 younger adults and 20 older adults. In different conditions, a single 80 dB SPL auditory stimulus was presented relatively rapidly, every 1.5 s or very slowly, every 12.0 s. Participants ignored the auditory stimuli while watching a silent video. When the stimuli were presented rapidly, group differences were not observed for the amplitudes of N1 and P2, which peaked at 100 and 180 ms respectively. When stimuli were presented very slowly, their amplitudes were much enhanced for younger adults, but did not increase for older adults. The failure to observe a large increase in the amplitude of N1 and P2 in older adults for very slowly presented auditory stimuli provides strong evidence of a dysfunction of the salience network in this group.


Subject(s)
Acoustic Stimulation , Aging/physiology , Evoked Potentials/physiology , Frontal Lobe/physiology , Nerve Net/physiology , Parietal Lobe/physiology , Adolescent , Aged , Electroencephalography , Female , Humans , Male , Time Factors , Young Adult
9.
J Pain ; 22(5): 545-555, 2021 05.
Article in English | MEDLINE | ID: mdl-33321196

ABSTRACT

Chronic low back pain (cLBP) has been associated with changes in brain plasticity. Nonpharmacological therapies such as Manual Therapy (MT) have shown promise for relieving cLBP. However, translational neuroimaging research is needed to understand potential central mechanisms supporting MT. We investigated the effect of MT on resting-state salience network (SLN) connectivity, and whether this was associated with changes in clinical pain. Fifteen cLBP patients, and 16 matched healthy controls (HC) were scanned with resting functional Magnetic Resonance Imaging (fMRI), before and immediately after a MT intervention (cross-over design with two separate visits, pseudorandomized, grades V 'Manipulation' and III 'Mobilization' of the Maitland Joint Mobilization Grading Scale). Patients rated clinical pain (0-100) pre- and post-therapy. SLN connectivity was assessed using dual regression probabilistic independent component analysis. Both manipulation (Pre: 39.43 ± 16.5, Post: 28.43 ± 16.5) and mobilization (Pre: 38.83 ± 17.7, Post: 31.76 ± 19.4) reduced clinical back pain (P < .05). Manipulation (but not mobilization) significantly increased SLN connectivity to thalamus and primary motor cortex. Additionally, a voxelwise regression indicated that greater MT-induced increase in SLN connectivity to the lateral prefrontal cortex was associated with greater clinical back pain reduction immediately after intervention, for both manipulation (r = -0.8) and mobilization (r = -0.54). Our results suggest that MT is successful in reducing clinical low back pain by both spinal manipulation and spinal mobilization. Furthermore, this reduction post-manipulation occurs via modulation of SLN connectivity to sensorimotor, affective, and cognitive processing regions. PERSPECTIVE: MT both reduces clinical low back pain and modulates brain activity important for the processing of pain. This modulation was shown by increased functional brain connectivity between the salience network and brain regions involved in cognitive, affective, and sensorimotor processing of pain.


Subject(s)
Chronic Pain/therapy , Connectome , Low Back Pain/therapy , Manipulation, Spinal , Motor Cortex/physiopathology , Nerve Net/physiopathology , Prefrontal Cortex/physiopathology , Thalamus/physiopathology , Adult , Chronic Pain/diagnostic imaging , Chronic Pain/physiopathology , Cross-Over Studies , Humans , Low Back Pain/diagnostic imaging , Low Back Pain/physiopathology , Magnetic Resonance Imaging , Middle Aged , Motor Cortex/diagnostic imaging , Nerve Net/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Thalamus/diagnostic imaging
10.
Cereb Cortex ; 31(4): 1970-1986, 2021 03 05.
Article in English | MEDLINE | ID: mdl-33253367

ABSTRACT

A complete picture of how subcortical nodes, such as the thalamus, exert directional influence on large-scale brain network interactions across age remains elusive. Using directed functional connectivity and weighted net causal outflow on resting-state fMRI data, we provide evidence of a comprehensive reorganization within and between neurocognitive networks (default mode: DMN, salience: SN, and central executive: CEN) associated with age and thalamocortical interactions. We hypothesize that thalamus subserves both modality-specific and integrative hub role in organizing causal weighted outflow among large-scale neurocognitive networks. To this end, we observe that within-network directed functional connectivity is driven by thalamus and progressively weakens with age. Secondly, we find that age-associated increase in between CEN- and DMN-directed functional connectivity is driven by both the SN and the thalamus. Furthermore, left and right thalami act as a causal integrative hub exhibiting substantial interactions with neurocognitive networks with aging and play a crucial role in reconfiguring network outflow. Notably, these results were largely replicated on an independent dataset of matched young and old individuals. Our findings strengthen the hypothesis that the thalamus is a key causal hub balancing both within- and between-network connectivity associated with age and maintenance of cognitive functioning with aging.


Subject(s)
Aging/physiology , Aging/psychology , Cerebral Cortex/physiology , Cognition/physiology , Nerve Net/physiology , Thalamus/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Cerebral Cortex/diagnostic imaging , Cohort Studies , Female , Humans , Magnetic Resonance Imaging/trends , Male , Middle Aged , Nerve Net/diagnostic imaging , Thalamus/diagnostic imaging , Young Adult
11.
Brain Struct Funct ; 225(5): 1537-1559, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32347366

ABSTRACT

Functional neuroimaging studies using auditory stimuli consistently show activation of the insular cortex. However, due to the limited temporal resolution of non-invasive neuroimaging techniques, the role(s) of the insula in auditory processing remains unclear. As the anterior insula (aI) and the posterior insula (pI) have different connections and are thought to be functionally distinct, it is likely that these two areas contribute differently to auditory processing. Our study examines the spatiotemporal dynamics of auditory processing in the insula using intracranial electroencephalography (EEG). Eight epileptic patients completed two passive listening tasks and one three-stimulus auditory oddball detection task during the intracranial EEG monitoring of their drug-resistant seizures. Recordings were obtained from depth electrodes implanted in 11 insulae. Event-related potentials (ERPs) were analyzed using permutation analyses during the N100 and the P300 intervals, and modulations of alpha, theta, and gamma band responses were compared using Wilcoxon/Mann-Whitney analyses. N100 responses to auditory stimuli were mostly observed in the pI and were little affected by task conditions. Auditory target detection was associated with P300 ERPs, and alpha, theta, high- and low-gamma responses, preferentially at aI contacts. Results suggest that the aI is involved in voluntary attentional processing of task-relevant information, whereas the pI is involved in automatic auditory processing.


Subject(s)
Auditory Perception/physiology , Cerebral Cortex/physiology , Evoked Potentials , Psychomotor Performance/physiology , Acoustic Stimulation , Adolescent , Adult , Electrodes, Implanted , Electroencephalography , Epilepsy/physiopathology , Epilepsy/psychology , Event-Related Potentials, P300 , Female , Humans , Male , Young Adult
12.
J Affect Disord ; 269: 43-50, 2020 05 15.
Article in English | MEDLINE | ID: mdl-32217342

ABSTRACT

BACKGROUND: Bipolar depression (BDD) and major depressive disorder (MDD) are two diseases both characterized by depressed mood and diminished interest or pleasure. Recent neuroimaging studies have implicated the thalamo-cortical circuit in mood disorders, and the present study aimed to map thalamo-cortical connectivity to explore the dissociable and common abnormalities between bipolar and major depression in this circuit. METHOD: Applying resting-state functional magnetic resonance imaging (fMRI), we mapped the thalamo-cortical circuit using a fine-grained thalamic atlas with 8 sub-regions bilaterally in 38 BDD patients, 42 MDD patients and 39 healthy controls (HCs). Correlation analysis was then performed between thalamo-cortical connectivity and clinical variables. RESULT: The findings showed that both patient groups exhibited prefronto-thalamo-cerebellar and sensorimotor-thalamic hypoconnectivity, while the abnormalities in MDD were more extensive. Particularly, MDD group showed decreased thalamic connectivity with the salience network including the insula, anterior cingulate cortex (ACC), and striatum. No correlations were found between the abnormal thalamo-cortical connectivity and clinical symptoms in either patient group. LIMITATION: Most patients in our study were taking drugs at the time of scanning, which may confound our findings. CONCLUSION: Our finding suggest that the thalamo-cortical hypofunction is a common neuro-substrate for BDD and MDD. Specifically, the hypoconnectivity between the thalamus and salience network including the insula, ACC and striatum may be a distinguished biomarker for MDD, which may help to differentiate these two emotional disorders.


Subject(s)
Bipolar Disorder , Depressive Disorder, Major , Bipolar Disorder/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Depressive Disorder, Major/diagnostic imaging , Humans , Magnetic Resonance Imaging , Thalamus/diagnostic imaging
13.
Schizophr Res ; 216: 382-388, 2020 02.
Article in English | MEDLINE | ID: mdl-31801675

ABSTRACT

Numerous studies strongly have suggested the significant role of serotonin in the pathomechanism of schizophrenia. However, few studies have directly explored the altered serotonin function in schizophrenia. In the current study, we explored the altered serotonin function in first-episode treatment-naive patients with schizophrenia with resting-state functional magnetic resonance imaging. A total 42 first-episode treatment-naive patients with schizophrenia and carefully matched healthy controls are included in the study. Considering that the raphe nucleus providing a substantial proportion of the serotonin innervation to the forebrain, the raphe nucleus was chosen as the seed to construct voxel-based functional connectivity (FC) maps. In the results, subcortical dopamine-related regions presented decreased FC with the raphe nucleus, such as the bilateral striatum, pallidum, and thalamus, in patients with schizophrenia. Decreased FC in these regions was significantly correlated with the total negative scores in PANSS. Furthermore, these regions presented with decreased FC connection to salience network. Our results presented that the raphe nucleus played an important role in the dysfunction of subcortical DA-related regions, and contributed to the altered salience network in schizophrenia. Our study emphasized the importance of the raphe nucleus in the pathophysiology of schizophrenia.


Subject(s)
Dopamine , Schizophrenia , Humans , Magnetic Resonance Imaging , Raphe Nuclei/diagnostic imaging , Schizophrenia/diagnostic imaging , Thalamus
14.
Brain Imaging Behav ; 14(5): 1350-1360, 2020 Oct.
Article in English | MEDLINE | ID: mdl-30689171

ABSTRACT

The disruption of salience network (SN) has been consistently found in patients with schizophrenia and thought to give rise to specific symptoms. However, the functional dysconnectivity pattern of SN remains unclear in first-episode schizophrenia (FES). Sixty-five patients with FES and sixty-six health controls (HC) were enrolled in this study and underwent resting-state functional magnetic resonance imaging (rs-fMRI). The eleven regions of interest (ROIs) within SN were derived from the peaks of the group independent component analysis (gICA). Seed-based whole-brain functional connectivity (FC) analyses were performed with all SN ROIs as the seeds. Both hyper- and hypo-connectivity of SN were found in the FES. Specifically, the increased FC mainly existed between the SN and cortico-cerebellar sub-circuit and prefrontal cortex, while the reduced FC mainly existed within cortico-striatal-thalamic-cortical (CSTC) sub-circuit. Our findings suggest that FES is associated with pronounced dysregulation of SN, characterized prominently by hyperconnectivity of SN-prefrontal cortex and cerebellum, as well as hypoconnectivity of CSTC sub-circuit of the SN.


Subject(s)
Schizophrenia , Brain Mapping , Cerebral Cortex , Humans , Magnetic Resonance Imaging , Neural Pathways/diagnostic imaging , Schizophrenia/diagnostic imaging , Thalamus
15.
Neuroimage Clin ; 28: 102490, 2020.
Article in English | MEDLINE | ID: mdl-33395981

ABSTRACT

OBJECTIVE: The default-mode network (DMN) and salience network (SN) have been shown to display altered connectivity in posttraumatic stress disorder (PTSD). Restoring aberrant connectivity within these networks with electroencephalogram neurofeedback (EEG-NFB) has been shown previously to be associated with acute decreases in symptoms. Here, we conducted a double-blind, sham-controlled randomized trial of alpha-rhythm EEG-NFB in participants with PTSD (n = 36) over 20-weeks. Our aim was to provide mechanistic evidence underlying clinical improvements by examining changes in network connectivity via fMRI. METHODS: We randomly assigned participants with a primary diagnosis of PTSD to either the experimental group (n = 18) or sham-control group (n = 18). We collected resting-state fMRI scans pre- and post-NFB intervention, for both the experimental and sham-control PTSD groups. We further compared baseline brain connectivity measures pre-NFB to age-matched healthy controls (n = 36). RESULTS: With regard to the primary outcome measure of PTSD severity, we found a significant main effect of time in the absence of a group × time interaction. Nevertheless, we found significantly decreased PTSD severity scores in the experimental NFB group only, when comparing post-NFB (dz = 0.71) and 3-month follow-up scores (dz = 0.77) to baseline measures. Interestingly, we found evidence to suggest a shift towards normalization of DMN and SN connectivity post-NFB in the experimental group only. Both decreases in PTSD severity and NFB performance were correlated to DMN and SN connectivity post-NFB in the experimental group. Critically, remission rates of PTSD were significant higher in the experimental group (61.1%) as compared to the sham-control group (33.3%). CONCLUSION: The current study shows mechanistic evidence for therapeutic changes in DMN and SN connectivity that are known to be associated with PTSD psychopathology with no patient dropouts. This preliminary investigation merits further research to demonstrate fully the clinical efficacy of EEG-NFB as an adjunctive therapy for PTSD.


Subject(s)
Neurofeedback , Stress Disorders, Post-Traumatic , Brain , Electroencephalography , Humans , Magnetic Resonance Imaging , Stress Disorders, Post-Traumatic/diagnostic imaging , Stress Disorders, Post-Traumatic/therapy
16.
Front Neurosci ; 13: 1062, 2019.
Article in English | MEDLINE | ID: mdl-31636536

ABSTRACT

The underlying mechanism of pain reduction by acupuncture is still unclear, because acupuncture treatment involves multidimensional factors. In this study, we investigated the differential influence of acupuncture components on brain functional connectivity and on pain reduction. We used a specific form of sham acupuncture (phantom acupuncture; PHNT), which only has a needling-credibility (a belief that they were treated with real acupuncture needles), while real acupuncture (REAL) has a somatosensory needling stimulation, as well as a needling-credibility. Forty-three patients with low back pain were randomized into the REAL group (n = 25) and the PHNT group (n = 18). They underwent two pain steady-state fMRI runs implemented by a low back extension (LBE) pain model (lifting the low back using air-cuff inflation) before and after REAL or PHNT stimulation. Subjective pain ratings, perceived throughout the LBE runs due to the posture, were reported (LBEpain). The regions of interest (ROI) were (1) the main nodes of the default mode network (DMN) - the medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), (2) the main nodes of the salience network (SN) - the anterior/posterior insular cortices (a/pINS), and (3) the low back-specific region of sensorimotor network (SMN), S1back. Significant reductions in LBEpain were observed in both groups (REAL = -1.02 ± 1.53, PHNT = -1.26 ± 2.20). In REAL group, decreased LBEpain was positively correlated with decreased functional connectivity between the mPFC and pINS (r = 0.58, P < 0.05). Reduced LBEpain in PHNT was negatively correlated with increased PCC-aINS connectivity (r = -0.48, P < 0.05) and tended toward positive correlation with decreased S1back-pINS connectivity (r = 0.44, P = 0.07). Our findings might suggest different brain mechanisms of observed pain reduction; REAL seems to involve detachment of the self from the sensory aspect of pain, while PHNT does to shift attention to self and disengages physical pain processing hubs. This exploratory study proposes a sham methodology to dissociate the influence of different acupuncture components in acupuncture research. Further studies need to be followed with more elaborated hypothesis, study design, and analysis considering various cognitive/affective factors for better understanding of brain mechanisms of pain reduction regarding the different acupuncture aspects.

17.
Neuropsychologia ; 134: 107226, 2019 11.
Article in English | MEDLINE | ID: mdl-31618619

ABSTRACT

BACKGROUND: Event-Related Potential (ERP) studies of PTSD have reported enhanced P3 amplitudes in response to trauma-related stimuli that are less likely to habituate over time. METHODS: In the present study, we compared ERPs to the first and last half of an auditory novelty oddball task using neutral (trauma-unrelated) stimuli. Participants were 59 young students who were: trauma-exposed with "Probable PTSD", trauma-exposed without PTSD, or non-traumatized controls. RESULTS: Reduced P3 amplitudes were observed for the last half of the trials for the entire sample, but this habituation was less profound for both trauma-exposed groups, demonstrating reduced habituation over time. Arousal symptom severity and trauma history negatively correlated with P3 amplitude habituation across the entire sample. Reduced N1 amplitudes for the last half of the trials were found in both trauma-exposed groups, but not among controls. CONCLUSIONS: Our findings suggest that trauma-exposed individuals exhibit information processing alterations in response to neutral environmental stimuli that may be related to a general pattern of heightened activity of the Salience Network. Implications for the neurobiological model of PTSD and PTSD psychotherapy are discussed.


Subject(s)
Habituation, Psychophysiologic , Nerve Net/physiopathology , Stress Disorders, Post-Traumatic/psychology , Wounds and Injuries/psychology , Acoustic Stimulation , Adult , Arousal , Electroencephalography , Evoked Potentials , Female , Humans , Male , Models, Psychological , Neuropsychological Tests , Young Adult
18.
Quant Imaging Med Surg ; 9(6): 1118-1125, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31367566

ABSTRACT

BACKGROUND: To explore the immediate effects and mechanism of acupuncture on craving after tobacco cessation based on the fractional amplitude of low-frequency fluctuation (fALFF). METHODS: This was a functional magnetic resonance imaging (fMRI) study. Forty participants were recruited and divided into a smoking group and a non-smoking group, 20 cases in each one. The smoking participants were requested to quit smoking 24 hours before the fMRI scan. The scan process was scan - acupuncture - scan. Between the two scans, acupuncture was applied at Lieque (LU 7), Hegu (LI 4), Baihui (GV 20), Zusanli (ST 36), Sanyinjiao (SP 6) and Taichong (LR 3) in two groups. RESULTS: After acupuncture, self-made craving for smoking, Minnesota Nicotine Withdrawal Scale (MNWS) and Questionnaire of Smoking Urges (QSU) were all reduced (P<0.05). The fMRI results indicated the immediate effects of acupuncture on smoking craving were significant, and identified salience network (SN) consisted of anterior cingulate cortex and insula, prefrontal cortex, visual cortex and cerebellum as key brains area. Correlation analysis indicated that NWNS scores were positively correlated with the mean fALFF in the ACC (P<0.05) and negatively correlated with the mean fALFF in the insula (P<0.05) in the smoking group. CONCLUSIONS: This was the first study in China to explore the neural mechanisms of acupuncture for smoking craving. The results indicated that the effects of acupuncture on smoking craving were significant, and the SN played a critical role in the process.

19.
Proc Natl Acad Sci U S A ; 116(24): 12103-12108, 2019 06 11.
Article in English | MEDLINE | ID: mdl-31138687

ABSTRACT

Neonatal intensive care units are willing to apply environmental enrichment via music for preterm newborns. However, no evidence of an effect of music on preterm brain development has been reported to date. Using resting-state fMRI, we characterized a circuitry of interest consisting of three network modules interconnected by the salience network that displays reduced network coupling in preterm compared with full-term newborns. Interestingly, preterm infants exposed to music in the neonatal intensive care units have significantly increased coupling between brain networks previously shown to be decreased in premature infants: the salience network with the superior frontal, auditory, and sensorimotor networks, and the salience network with the thalamus and precuneus networks. Therefore, music exposure leads to functional brain architectures that are more similar to those of full-term newborns, providing evidence for a beneficial effect of music on the preterm brain.


Subject(s)
Cognition/physiology , Infant, Premature/physiology , Neural Pathways/physiology , Parietal Lobe/physiology , Thalamus/physiology , Female , Humans , Infant, Newborn , Magnetic Resonance Imaging/methods , Male , Music , Nerve Net/physiology
20.
Brain Struct Funct ; 224(6): 2045-2059, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31129871

ABSTRACT

Functional neuroimaging studies suggest that the insular cortex-and more especially the anterior insula (aI)-is involved in attentional processes and plays a crucial role in the "salience network". However, its specific role in attentional processing remains unclear, which is partly attributable to the low temporal resolution of non-invasive neuroimaging techniques. This study aims to examine the spatio-temporal dynamics of visual target processing using intracranial EEG recorded directly from the insula. Eight epileptic patients (four women, age 18-44 years) completed a three-stimulus visual oddball task during the extraoperative invasive intracranial EEG (iEEG) monitoring of their drug-resistant seizures. Depth electrodes were implanted in ten insular lobes (5 left and 5 right) and provided a total of 59 recording contacts in the insula. Event-related potentials (ERPs) and high-gamma-band responses (GBRs) were processed offline. Permutation analyses were performed to compare ERP signals across conditions during the P300 (225-400) interval, and modulations of GBRs (70-150 Hz) were computed for separate 100 ms time windows (from 0 to 1000 ms post-stimulus) and compared across conditions using non-parametric Wilcoxon test. Target stimuli were associated with a P300 (250-338 ms) component for 39% of contacts implanted in the aI, most probably reflecting voluntary attentional processing. Amplitude was significantly greater for target than for standard stimuli for all of these contacts, and was greater than for novel stimuli for 72%. In the posterior insula (pI), 16% of contacts showed preferential responses to target stimulus in the P300 interval. Increased GBRs in response to targets were observed in 53% of aI contacts (from ≈ 200 to 300 ms) and in 43% of pI contacts (from ≈ 400 to 500 ms). This study is the first to characterize the spatio-temporal dynamics of visual target processing in the insula using iEEG. Results suggest that visual targets elicit a P300 in the aI which corresponds in latency to the P3b component, suggesting that this region is involved in top-down processing of task-relevant information. GBRs to visual targets occur earlier in the aI than in the pI, further characterizing their respective roles in voluntary attentional processing.


Subject(s)
Attention/physiology , Cerebral Cortex/physiopathology , Epilepsy/physiopathology , Evoked Potentials/physiology , Acoustic Stimulation/methods , Adolescent , Adult , Brain Mapping/methods , Cognition/physiology , Electroencephalography/methods , Female , Humans , Male , Photic Stimulation/methods , Reaction Time/physiology , Young Adult
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